Mach 2 Supersonic Combustion with Hydrocarbon Fuels in a Rectangular Scramjet Combustor

摘要

Experimental investigations were carried out with liquid kerosene, gaseous methane and hydrogen as fuels, which were injected into Mach 2 scramjet combustor with the step/cavity. The flame behavior of each fuel was investigated through wall pressure measurements and optical measurements. The self-ignition occurred in the far-field. However the hydrocarbon fuel was not able to burn even in the hot boundary layer, so that it was difficult for hydrocarbon flame to propagate to the near-field such as the step or the cavity, which was one of the problems of hydrocarbon fuels. On the other hand, once the flame moved to the near-field and was anchored by the separation bubble generated by the PSW at the cavity, the kerosene flame was held stably. However, the separation bubble was unstable so that it was blown off easily. The stabilization of the separation bubbles is the key to the stable flame-holding for hydrocarbon fuel.